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SUMMARY In plants, RNA silencing constitutes a strong defense against viral infection, which viruses counteract with RNA‐silencing suppressors (RSSs). Understanding the interactions between viral RSSs and host factors is crucial for elucidating the molecular arms race between viruses and host plants. We report that the helicase motif (Hel) of the replicase encoded by apple stem grooving virus (ASGV)—the main virus affecting pear trees in China—is an RSS that can inhibit both local and systemic RNA silencing, possibly by binding double‐stranded (ds) siRNA. The transcription factor related to ABSCISIC ACID INSENSITIVE3/VIVIPAROUS1 from pear (PbRAV1) enters the cytoplasm and binds Hel through its C terminus, thereby attenuating its RSS activity by reducing its binding affinity to 21‐ and 24‐nt ds siRNA, and suppressing ASGV infection. PbRAV1 can also target p24, an RSS encoded by grapevine leafroll‐associated virus 2 (GLRaV‐2), with similar negative effects on p24's suppressive function and inhibition of GLRaV‐2 infection. Moreover, like the positive role of the PbRAV1 homolog from grapevine (VvRAV1) in p24's previously reported RSS activity, ASGV Hel can also hijack VvRAV1 and employ the protein to sequester 21‐nt ds siRNA, thereby enhancing its own RSS activity and promoting ASGV infection. Furthermore, PbRAV1 neither interacts with CP, an RSS encoded by grapevine inner necrosis virus, nor has any obvious effect on CP's RSS activity. Our results identify an RSS encoded by ASGV and demonstrate that PbRAV1, representing a novel type of RAV transcription factor, plays a defensive role against viral infection by targeting viral RSSs. [ABSTRACT FROM AUTHOR]

Mutation of DOMAIN OF UNKNOWN FUNCTION 679 MEMBRANE PROTEIN in cucumber induces in vivo maternal haploids and suggests prospects for cucurbit breeding. [ABSTRACT FROM AUTHOR]

Local constraint in the lattice gauge theory provides an exotic mechanism that facilitates the disorder-free localization. However, the understanding of nonequilibrium dynamics in the non-Hermitian lattice gauge model remains limited. Here, we investigate the quench dynamics in a system of spinless fermions with nonreciprocal hopping in the Z 2 gauge field. By employing a duality mapping, we systematically explore the non-Hermitian skin effect, localization-delocalization transition, and real-complex transition. Through the identification of diverse scaling behaviors of quantum mutual information for fermions and spins, we propose that the non-Hermitian quantum disentangled liquids exist both in the localized and delocalized phases, the former originates from the Z 2 gauge field and the latter arises from the non-Hermitian skin effect. Furthermore, we demonstrate that the nonreciprocal dissipation causes the flow of quantum information. Our results provide valuable insights into the nonequilibrium dynamics in the gauge field, and may be experimentally validated using quantum simulators. Lattice gauge theory, a subset of gauge theory, has been successfully applied to a range of quantum systems allowing for the investigation of localised phenomena within these systems. Here, the authors consider a non-Hermitian lattice model observing a quantum disentangled liquid state that exists in both the localised and delocalised phases. [ABSTRACT FROM AUTHOR]

Cucumber is an economically important vegetable crop, and the warts (composed of spines and Tubercules) of cucumber fruit are an important quality trait that influences its commercial value. WOX transcription factors are known to have pivotal roles in regulating various aspects of plant growth and development, but their studies in cucumber are limited. Here, genome-wide identification of cucumber WOX genes was performed using the pan-genome analysis of 12 cucumber varieties. Our findings revealed diverse CsWOX genes in different cucumber varieties, with variations observed in protein sequences and lengths, gene structure, and conserved protein domains, possibly resulting from the divergent evolution of CsWOX genes as they adapt to diverse cultivation and environmental conditions. Expression profiles of the CsWOX genes demonstrated that CsWOX9 was significantly expressed in unexpanded ovaries, especially in the epidermis. Additionally, analysis of the CsWOX9 promoter revealed two binding sites for the C2H2 zinc finger protein. We successfully executed a yeast one-hybrid assay (Y1H) and a dual-luciferase (LUC) transaction assay to demonstrate that CsWOX9 can be transcriptionally activated by the C2H2 zinc finger protein Tu, which is crucial for fruit Tubercule formation in cucumber. Overall, our results indicated that CsWOX9 is a key component of the molecular network that regulates wart formation in cucumber fruits, and provide further insight into the function of CsWOX genes in cucumber. [ABSTRACT FROM AUTHOR]

Understanding reservoir, source, seal, migration pathways and trap characterization is the first step towards better energy resource exploitation. Several studies have been conducted in recent decades on the reservoir characteristics of conventional resources. Unconventional resources, on the other hand, have received more attention as alternative future energy solutions to depleted conventional resources. Drilling, exploration, development, and production of conventional and unconventional resources pose technical challenges to the energy industry. This special issue attempts to address the most pressing technical challenges in developing conventional reservoirs (such as sandstone and carbonate reservoirs) as well as unconventional energy sources (e.g., shale gas, shale oil, tight gas sand, coal bed methane, geothermal and gas hydrates). The special issue is composed of 21 papers that are classified into six different groups related to the physical and mechanical properties of reservoirs, petroleum geochemistry, petroleum geology, geological modelling, unconventional resource evaluation and conventional reservoir evaluation. [ABSTRACT FROM AUTHOR]

Background: Acupuncture has been used to relieve chronic pain in patients with knee osteoarthritis (KOA), but the evidence is contradictory. Therefore, we carefully designed a double-dummy randomized controlled trial (RCT) to explore the therapeutic effect of acupuncture for KOA. Methods/design: A total of 138 eligible participants with KOA who consent to participate will be randomly divided into Groups A, B, and C in a ratio of 1:1:1. Participants in Group A will receive verum acupuncture and placebo gel, while those in Groups B and C will be treated with diclofenac diethylammon gel and sham acupuncture, sham acupuncture and placebo gel, respectively. The patients will receive 4 weeks of treatment, five times a week, including acupuncture treatment once a day for 30 min and gel treatment three times a day. The primary outcome will be the change of Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) at week 4. The secondary outcomes will include visual analog scale (VAS), Arthritis Quality of Life Measurement Scale Simplified Scale (AIMS2-SF), Beck Anxiety Inventory (BAI), Beck Depression Inventory (BDI) and Credibility/Expectancy Questionnaire. The evaluation will be performed at baseline, week 4, 8, and 12 after randomization. Discussion: This double-dummy RCT used diclofenac diethylammon gel as a positive control, and the completion of this trial will provide detailed and accurate evidence of the efficacy and safety of acupuncture for KOA. Trial registration: China Clinical Trials Registry No.ChiCTR2100043947. Registered on September 24, 2020. https://www.chictr.org.cn/showproj.html?proj=122536. [ABSTRACT FROM AUTHOR]

Phototheranostics that concurrently integrates accurate diagnosis (e.g., fluorescence and photoacoustic (PA) imaging) and in situ therapy (e.g., photodynamic therapy (PDT) and photothermal therapy (PTT)) into one platform represents an attractive approach for accelerating personalized and precision medicine. The second near-infrared window (NIR-II, 1000–1700 nm) has attracted considerable attention from both the scientific community and clinical doctors for improved penetration depth and excellent spatial resolution. NIR-II agents with a PDT property as well as other functions are recently emerging as a powerful tool for boosting the phototheranostic outcome. In this minireview, we summarize the recent advances of photodynamic NIR-II aggregation-induced emission luminogens (AIEgens) for biomedical applications. The molecular design strategies for tuning the electronic bandgaps and photophysical energy transformation processes are discussed. We also highlight the biomedical applications, such as image-guided therapy of both subcutaneous and orthotopic tumors, and multifunctional theranostics in combination with other treatment methods, including chemotherapy and immunotherapy; and the precise treatment of both tumor and bacterial infection. This review aims to provide guidance for PDT agents with long-wavelength emissions to improve the imaging precision and treatment efficacy. We hope it will provide a comprehensive understanding about the chemical structure–photophysical property–biomedical application relationship of NIR-II luminogens. [ABSTRACT FROM AUTHOR]

The migration of plasticizers such as nitroglycerin seriously affects the storage and working safety of rocket systems. In this work, hydroxy-terminated polybutadiene (HTPB) liner composites with the cross-linked structure were prepared by cross-linking isocyanate functionalized graphene oxide (IGO) with HTPB to prevent the migration of high energy plasticizers in the propellant. IGO was uniformly dispersed in the matrix as reinforcement and cross-linker, providing good migration resistance and ablation resistance for the liner composites. Compared with pure HTPB, the migration resistance of the liner with 0.5 wt% IGO increased by 18.94%, 16.33% and 15.34% at 25 °C, 60 °C and 90 °C, respectively. In addition, the ablation resistance of the HTPB liner was improved by the addition of IGO. The improved anti-migration properties come from the special laminar structure of IGO and the dense molecular chains network of the cross-linked composites. [ABSTRACT FROM AUTHOR]

As a highly toxic commercial product, phosgene is a potentially serious threat to public safety, so a convenient and reliable phosgene detection method is urgently needed. In this work, a new through-bond energy transfer (TBET) based fluorescent probe TPE–RhodEA has been developed as a fast, susceptible, and selective sensor of phosgene. TPE–RhodEA is based on a tetraphenylethylene–rhodamine scaffold and uses ethylenediamine as the phosgene recognition unit. The probe showed blue fluorescence in acetonitrile due to the occlusion of rhodamine diamine. After reacting with phosgene, rhodamine diamine undergoes ring-opening, and TPE–RhodEA exhibits apparent red fluorescence. Due to the specific ring-opening reaction, TPE–RhodEA shows a distinct ratiometric fluorescence response to phosgene with a significant pseudo Stokes shift (267 nm), an immediate response (less than 2 min), and a low detection limit (0.54 ppm). Furthermore, TPE–RhodEA-loaded test TLC strips were prepared and enabled the direct visualization and reliable quantitative analysis of phosgene by combining fluorescent test TLC strips with an easily accessible color recognition app on a smartphone. [ABSTRACT FROM AUTHOR]

[Display omitted] Multilayer capsules not only provide better protection for the core, but also enable multifunctionalities. However, their fabrication is challenging. Rapid encapsulation by the impact of the droplet is a simplified approach to form the compound droplet with a single shell layer. Therefore, it is worth exploring the potential for multilayer capsule formation with the approach. We investigate the impact of an aqueous core droplet through a layered liquid pool to form compound droplet and use ultraviolet polymerization to solidify its outer layer. The critical conditions to form the compound droplet are studied. We then explore the protection features of the capsule. We succeed in fabricating defect-free capsules that featuring a triple-layered structure with a solid outer shell. The corresponding formation dynamics is revealed. We illustrate that the capsule provides reliable protection to the core through fluorescent intensity monitoring, pH level indication and bacteria revival test. Our method can also be adapted to tailor the functionality of the capsule, which is demonstrated by fabricating the magnetically steerable capsule. Our proposed approach offers great potentials for protecting sensitive ingredients and allows great flexibility in customizing capsule functionalities. [ABSTRACT FROM AUTHOR]

Long noncoding RNAs (lncRNAs) have been shown to be involved in the development of osteoarthritis. However, the expression, function, and mechanism of DLEU1 in OA development remain largely unclear. The present reference demonstrates that DLEU1 is overexpressed in OA specimens compared to control cartilages. Inflammatory cytokines IL-1β, TNF-α, and IL-6 induce DLEU1 expression in chondrocytes. Ectopic expression of DLEU1 induces chondrocyte proliferation, degradation of ECM, and inflammation mediators such as IL-6, IL-8, and TNF-α secretion. Moreover, we demonstrated that DLEU1 targets miR-671-5p expression in chondrocytes. Overexpression of DLEU1 suppresses miR-671-5p expression in chondrocytes. The expression of miR-671-5p is decreased in OA specimens compared to control cartilages. There is a negative correlation between the expression of miR-671-5p and DLEU1 in OA specimens. Inflammatory mediators IL-1β, TNF-α, and IL-6 suppress miR-671-5p expression in OA specimens. Elevated expression of miR-671-5p suppresses chondrocyte proliferation, degradation of ECM, and secretion of inflammation mediators. DLEU1 overexpression promotes chondrocytes proliferation, degradation of ECM, and secretion of inflammation mediators via regulating miR-671-5p. These results suggested that DLEU1 acts as one destructive role in OA development via regulating miR-671-5p. [ABSTRACT FROM AUTHOR]

The cumulative forecasting errors of wind and photovoltaic (PV) power pose serious challenges to the short-term scheduling of hydropower stations that connected to the same regional power grid. The variable and intermittent nature of wind and PV power necessitate a flexible power source to achieve power balance. Consequently, hydropower, with its flexible adjustment capability, plays a crucial role in supporting the consumption of wind and PV power stations in short-term scheduling. Meanwhile, to address the grid's peak shaving requirement, the scheduling of cascaded hydropower system becomes increasingly complex. Given the limitations of current wind and PV power output prediction technologies, achieving precise forecast remains challenging. In practice, the actual outputs of wind and PV power stations often diverge considerably from predicted values over multiple consecutive periods. This variability may result in the underutilization of wind and PV power if the reserve capacity of hydropower stations is insufficient. Therefore, it is essential to account for the cumulative deviation in electricity from wind and PV sources. By computing probability distribution and establishing boundary condition of the cumulative deviation, the operation of the cascaded hydropower system can be controlled more effectively, thus enhancing the stability of a multi-energy complementary system. This study employs Gaussian Mixture Model (GMM) to characterize the probability distributions of cumulative electricity deviation across multiple periods of wind and PV power and takes it as restriction to regulate the operation of hydropower stations. In order to balance the deviation electricity, the downward electricity reserve, upward electricity reserve and the storage energy of the cascaded reservoirs are introduced as restrictive conditions. The proposed Hydro-wind-PV peak shaving model is then applied to the short-term optimal scheduling of the Lancang River cascaded hydropower system to validate the feasibility and efficacy. • The impact of deviation energy of wind and PV power over multiple consecutive periods was considered; • Introduced the storage energy of hydropower to balance power shortages and power surplus from wind and PV stations; • The proposed hydro-wind-PV scheduling model is effective in peak shaving and promoting the utilization of wind and PV power. [ABSTRACT FROM AUTHOR]

YABBY transcription factors play important roles in plant growth and development. However, little is known about YABBY genes in Cucurbitaceae. Here, we identified 59 YABBY genes from eight cucurbit species, including cucumber (C. sativus L.), melon (C. melon L.), watermelon (C. lanatus), wax gourd (B. hispida), pumpkin (C. maxima), zucchini (C. pepo L.), silver-seed gourd (C. argyrosperma), and bottle gourd (L. siceraria). The 59 YABBY genes were clustered into five subfamilies wherein the gene structures and motifs are conserved, suggesting similar functions within each subfamily. Different YABBY gene numbers in eight cucurbit species indicated that gene loss or duplication events exist in an evolutionary process across Cucurbitaceae. The cis-acting elements analysis implied that the YABBYs may be involved in plant development, and phytohormone, stress, and light responses. Importantly, YABBY genes exhibited organ-specific patterns in expression in cucumber. Furthermore, a gene CsaV3_6G038650 was constitutively expressed at higher levels at different fruit development stages and might play a crucial role in cucumber fruit development. Collectively, our work will provide a better understanding for further function identifications of YABBY genes in Cucurbitaceae. [ABSTRACT FROM AUTHOR]

Skirted spudcan foundations can effectively provide a considerable bearing capacity and moment fixity to withstand the complex combined vertical, horizontal, and moment loadings encountered in offshore engineering practices. The failure envelope is a general solution that characterizes the bearing capacities of offshore foundations under combined loading conditions. In this study, a series of probe tests were carried out using finite element analysis to investigate the undrained failure envelope of skirted spudcan foundations in soft clay. Particular attention was paid to exploring the influences of the soil strength heterogeneity, the footing–soil interface roughness, and the embedment depth ratio. The analysis results indicate that the envelope's size is influenced by these conditions to varying degrees, while the envelope's shape is only slightly influenced. The failure envelope associated with smooth interface conditions provides conservative results, particularly for the deeply embedded scenarios. A closed-form algebraic expression was derived to describe the failure envelope of skirted spudcan foundations, which takes proper account of the soil strength heterogeneity, footing–soil interface roughness, and embedment depth ratio. [ABSTRACT FROM AUTHOR]

Key message: Two CO paralogs in Brassica napus were confirmed and shown distinct expression pattern and function in promoting flowering and allelic variation s within BnaCO.A10 were found closely associated with ecotype divergence. CONSTANS (CO) is a key gene that responds to photoperiod and in Arabidopsis can promote flowering under long-day (LD) conditions. Brassica napus L. is a major oil crop and close relative of Arabidopsis, and arose via allopolyploidization from the diploids B. rapa (A genome) and B. oleracea (C genome). In this study, we confirmed that B. napus has two CO genes located on the A10 (BnaCO.A10) and C9 (BnaCO.C9) chromosomes. Significant differences in level and temporal pattern of transcription, as well as in protein function, of these homoeologous may have resulted from sequence variation in the promoter as well as in the coding region. Apart from two insertions of 527 bp and 2002 bp in the promoter of BnaCO.C9 that function as transcriptional enhancers, this gene is otherwise highly conserved in both promoter and coding region. However, BnaCO.A10 was classified into two haplotypes and transgene analysis in Arabidopsis and backcross analysis in rapeseed indicated that the winter-type haplotype had a greater effect in promoting flowering than the spring type. We discuss the contribution of CO alleles to species evolution, and for eco-geographic radiation following crop domestication, alongside scope for managing this locus in future breeding. [ABSTRACT FROM AUTHOR]

Symmetry breaking plays a pivotal role in modern physics. Although self-similarity is also a symmetry, and appears ubiquitously in nature, a fundamental question arises as to whether self-similarity breaking makes sense or not. Here, by identifying an important type of critical fluctuation, dubbed 'phases fluctuations', and comparing the numerical results for those with self-similarity and those lacking self-similarity with respect to phases fluctuations, we show that self-similarity can indeed be broken, with significant consequences, at least in nonequilibrium situations. We find that the breaking of self-similarity results in new critical exponents, giving rise to a violation of the well-known finite-size scaling, or the less well-known finite-time scaling, and different leading exponents in either the ordered or the disordered phases of the paradigmatic Ising model on two- or three-dimensional finite lattices, when subject to the simplest nonequilibrium driving of linear heating or cooling through its critical point. This is in stark contrast to identical exponents and different amplitudes in usual critical phenomena. Our results demonstrate how surprising driven nonequilibrium critical phenomena can be. The application of this theory to other classical and quantum phase transitions is also anticipated. [ABSTRACT FROM AUTHOR]

In Brassicaceae, the requirement for vernalization is conferred by high expression of FLOWERING LOCUS C (FLC). The expression of FLC is known to be repressed by prolonged exposure to cold. Rapeseed (Brassica napus L.) cultivars can be classified into spring, winter, and semi-winter crop types, depending on their respective vernalization requirements. In addition to two known distinct transposon insertion events, here we identified a 4.422 kb hAT and a 5.625 kb long interspersed nuclear element transposon insertion within BnaFLC.A10 , and a 810 bp miniature inverted-repeat transposable element (MITE) in BnaFLC.A2. Quantitative PCR demonstrated that these insertions lead to distinct gene expression patterns and contribute differentially to the vernalization response. Transgenic and haplotype analysis indicated that the known 621 bp MITE in the promoter region of BnaFLC.A10 is a transcriptional enhancer that appears to be the main determinant of rapeseed vernalization, and has contributed to the adaptation of rapeseed in winter cultivation environments. In the absence of this transposon insertion, the functional allele of BnaFLC.A2 is a major determinant of vernalization demand. Thus, the combination of BnaFLC.A10 carrying the 621 bp MITE insertion and a functional BnaFLC.A2 appears necessary to establish the winter rapeseed crop phenotype. [ABSTRACT FROM AUTHOR]

• Established a three-dimensional physical model with high simulation accuracy. • The influence of different parameters on dust control was analyzed. • The optimal dustproof parameters of the driving area of the roadheader are obtained. • The CFD simulation was validated by field measurement. During coal mining, the fully-mechanized tunnel is always under high-concentration of dust pollution. This brings not only the potential risk of dust explosion but also makes the tunnel workers suffer from coal mine pneumoconiosis (CWP), a systemic disease featured by pulmonary fibrosis. Therefore, it is extremely important to establish a theory and optimal parameters for dust control over fully-mechanized excavating tunnels. In this study, we analyzed the dust diffusion under several parameters, including the distance between the forced air opening and the cutting face (L Y), the height of the forced air cylinder above the floor (L H), and the distance between the center of the forced air cylinder and the nearest coal wall (L J). The optimal dust control parameters were determined as: L Y = 20 m, L H = 3 m and L J = 0.6 m. Under this condition, the airflow can effectively suppress the diffusion of dust particles. At the same time, the operating environment of the roadheader driver was remarkably improved and the requirements on miners' occupational health and safe production were satisfied. The present study proposed a new approach for occupational health of the workers in the excavating tunnel and clean production management. [ABSTRACT FROM AUTHOR]

Highly active, durable oxygen reduction reaction (ORR) electrocatalysts have an essential role in promoting the continuous operation of advanced energy technologies such as fuel cells and metal–air batteries. Considering the scarce reserve of Pt and its unsatisfactory overall performance, there is an urgent demand for the development of new generation ORR electrocatalysts that are substantially better than the state-of-the-art supported Pt-based nanocatalysts, such as Pt/C. Among various nanostructures, bimetallic PtAu represents one unique alloy system where highly contradictory performance has been reported. While it is generally accepted that Au may contribute to stabilizing Pt, its role in modulating the intrinsic activity of Pt remains unclear. This perspective will discuss critical structural issues that affect the intrinsic ORR activities of bimetallic PtAu, with an eye on elucidating the origin of seemingly inconsistent experimental results from the literature. As a relatively new class of electrodes, we will also highlight the performance of dealloyed nanoporous gold (NPG) based electrocatalysts, which allow a unique combination of structural properties highly desired for this important reaction. Finally, we will put forward the challenges and opportunities for the incorporation of these advanced electrocatalysts into membrane electrode assemblies (MEA) for actual fuel cells. [ABSTRACT FROM AUTHOR]

In this paper, the gas composition and isotopic characteristics of the tight sandstone of the Upper Triassic Xujiahe Formation in the western Sichuan depression were analyzed, and the origin of hydrocarbon gas, rare gas and CO2 in natural gas were determined. The hydrocarbon gas content in the tight sandstone gas of the Xujiahe Formation is the highest, ranging from 96.43% to 99.44 vol.%, while the non-hydrocarbon gas content is only 0.34–2.73 vol.%. The hydrocarbon gas has the highest content of CH4, which is distributed from 88.52% to 97.86 vol.%, and the content of other hydrocarbon gases is relatively low. The studied natural gas is mainly dry gas, and a small part is wet gas. According to the hydrocarbon gas component and carbon isotope analysis results, it showed that the natural gas of the Xujiahe Formation was a thermogenic gas, and there was no mixing of biogenetic gas. The natural gas was derived from the thermal degradation of the humus kerogen. Moreover, the rare gas in the natural gas of the Xujiahe Formation is a crustal origin organic gas, and there is no mantle origin gas, which indicates the lack of inorganic components in the natural gas. We also found that the CO2 in the natural gas is mainly inorganic gas, which is derived from the dissolution of carbonate minerals; and only a small part is organic thermogenic gas, which is derived from the thermal maturation process of organic matter. [ABSTRACT FROM AUTHOR]

In recent years, a large number of vertical and horizontal sliding fractures were found in the Upper Palaeozoic sandstones in the eastern margin of the Ordos Basin, China, However, the effect of fractures on the distribution of tight sandstone gas is still unclear. Therefore, in this paper, a large number of cores, thin sections, petrophysical property test results, conventional and FMI (Formation MicroScanner Image) image logs, and gas‐testing results were used to study the developmental characteristics of fractures and the gas control effects in a tight sandstone reservoir, in the eastern margin of the Ordos Basin. It was found that the average linear density of the core fractures is generally less than 2 m−1, and the microfractures are characterized as ruptures of quartz particles. The underlying Taiyuan and Benxi formations have the highest fracture development degrees, and the fracture index (FI) values are 0.68 and 0.72, respectively. However, the fracture development degrees in the overlying Shanxi to Shiqianfeng formations are significantly lower, and the FI values are generally less than 0.63. There is a good positive correlation between the fracture development degree and the contents of quartz mineral or brittle minerals (quartz + feldspar). On the whole, the fractures in the uplift and slope parts of the low‐amplitude structure areas are more developed, while in the depression zones, the fractures are generally less developed. The fractures in the Zijinshan Uplift area are extremely well developed; thus, the preservation conditions of the reservoir are poor. In this case, the fractures are unfavourable for the accumulation of natural gas. For the gentle tectonic zones, the over‐developed fractures in the Benxi and Taiyuan formations are unfavourable for the preservation of natural gas. However, the moderately developed fractures in the overlying Shanxi to Shiqianfeng formations are beneficial to the enrichment of natural gas. Finally, we compared the relationship between fracture index (FI) and open‐flow productivity of the gas wells, and it was found that FI values of commercial gas wells (Types I, II, and III gas wells) are generally greater than 0.55, while the FI values of Type IV low‐yield gas wells are generally less than 0.55. [ABSTRACT FROM AUTHOR]

Ammonia (NH3) is a pivotal component for the majority of fertilizers, chemicals, and pharmaceuticals. Its conventional production through the Haber–Bosch process is highly energy-intensive and significantly contributes to CO2 emissions, thereby exacerbating global warming. In parallel, the overuse of agricultural fertilizers and the inadequate industrial wastewater management cause the heavy nitrate (NO3−) pollution which poses huge environmental and health hazards to human beings. In an effort to address these challenges, scientists have been exploring more sustainable methods of ammonia synthesis and strategies to mitigate nitrate pollution. Among these, the electrocatalytic reduction of nitrates to ammonia/ammonium (NO3RR) presents a promising solution. This innovative approach not only reduces the environmental footprint of ammonia production by operating under ambient conditions but also contributes to the purification of water bodies by lowering nitrate levels. This review intricately explores the complexities involved in the electrocatalytic reduction of nitrates to ammonia, shedding light on the nuanced mechanisms underlying the process and elucidating the importance of symmetry-breaking structures. It particularly underscores the pivotal role played by various symmetry-breaking structures in catalysts, which serve to disrupt and invigorate the reaction environment, thus enhancing the efficiency of the electrocatalytic process. In culmination, we offer a comprehensive summary of the advancements in the development of catalysts featuring symmetry-breaking structures, providing insights and forward-looking recommendations for the future engineering of broadly applicable symmetry-breaking structure catalysts. [ABSTRACT FROM AUTHOR]

Across the globe, the formation of large oil and gas fields is always associated with a wide range of anhydrite cap rocks. Thus, an accurate analysis of the dynamic and static mechanical properties of anhydrite rocks is required. A deep thick anhydrite cap rock is developed in the Paleogene formation of the southwestern Tarim Basin, NW China. In this paper, we designed mechanical and acoustic synchronization tests and acquired the corresponding parameters. The effects of stress and mineral composition on the dynamic and static mechanical properties of the anhydrite rock were analyzed systematically. The results indicate that under uniaxial conditions, the anhydrite rock showed obvious brittle rupture characteristics, while under triaxial conditions, the shear rupture characteristics were obvious. The stress–strain curves of the anhydrite rocks under triaxial conditions can be divided into five stages: initial compression stage, linear elasticity stage, nonlinear steady extension stage, nonlinear unsteady extension and failure stage and post-peak stress stage. An increase in the anhydrite content can delay the weakening time of the anhydrite rocks, greatly improving the rock strength. Under high-stress conditions, the anhydrite mineral particles can accumulate large amounts of energy, exhibit a long period of creep behavior and produce significant additional stresses. The anhydrite composition can improve the strength and rigidity of the anhydrite rocks. However, anhydrite rock with a high anhydrite content will also have strong plasticity. The greater the stress environment that the anhydrite rock bears, the stronger its plasticity will be. The anhydrite component can improve the ability of the anhydrite rocks to resist shear rupture. Compared to the anhydrite mudrocks (AMR), argillaceous anhydrite rocks (AR) have higher VP, VS and VP/VS values. There is a very good positive correlation between VP/VS and the anhydrite content. A regression model of the longitudinal and shear wave time differences of the anhydrite rocks is obtained, which can be used for the prediction of the shear wave time difference. The dynamic Young's modulus, Poisson's ratio and shear modulus of the AR are higher than those of the AMR. The regression models of dynamic and static mechanical parameters of the anhydrite rocks are also obtained. These models will be valuable in the evaluation of mechanical characteristics for similar types of anhydrite rocks worldwide. [ABSTRACT FROM AUTHOR]

The mobile jack-up drilling rigs supported by individual foundations are gradually extended to deep water for drilling activities in the offshore industry. These individual foundations are expected to provide considerable bearing capacity and moment fixity to ensure the entire system safety under the combined vertical, horizontal and moment loadings. Spudcan fitted with skirt at deep embedment may provide additional capacity to meet these demands. This paper carries out a series of probe tests using finite element analysis to investigate the potential benefits of deeply embedded skirted spudcan foundations under combined loading in soft clay. Four discrete skirt aspect ratios are considered to discuss the effects of the skirt length on the various bearing capacities. The failure envelopes for each of them are presented to identify the potential benefits. The results show that both the size and the shape of the failure envelopes changed greatly with increasing skirt aspect ratio. A modified analytical expression related to the skirt aspect ratio is proposed to interpret and predict the behavior of deeply embedded skirted spudcan foundations. • The potential benefits of deeply embedded skirted spudcan foundations under combined loading in soft clay were investigated. • The effects of the skirt length on the various bearing capacities were discussed. • The size and the shape of the failure envelopes changed greatly with increasing skirt aspect ratio. • A modified analytical expression related to the skirt aspect ratio is proposed. [ABSTRACT FROM AUTHOR]

Both the deformation and rupture characteristics of rocks are related to geomechanics. In this paper, we identify the evaluation indexes related to coalbed methane (CBM) accumulation in strongly deformed strike-slip fault zones considering tectonics and fractures. We found that fault scale, the fault combination, the tectonic stress, the preservation conditions and fractures all have important effects on the CBM distribution. Areas near the large-scale opening faults are unfavourable to the preservation of coalbed methane. The distribution of gas wells with different capacities is influenced by tectonic extension and convergence. A 3D geomechanical method was used to analyse the influence of the 'ribbon effect' of strike-slip faults on the CBM distribution. Due to the influence of the 'ribbon effect', the tectonic stress presents a plane in situ stress heterogeneity, which in turn will affect the gas well productivity. We also calculated the integrated rupture rate (I F) to characterize the degree of tectonic fracture development in the target coal reservoir. The appropriate fracture development degree can improve the petrophysical properties of the coal reservoirs while maintaining good storage conditions, such that the gas wells can achieve a higher production capacity. This study is of great significance for the enrichment of the geomechanical theory of oil and gas exploration. [ABSTRACT FROM AUTHOR]

Abstract Nanoporous gold (NPG) with three-dimensional bi-continuous structure have attracted many attentions ascribed to their desirable material characteristics, such as high surface area, high conductivity and outstanding chemical stability, especially for electrocatalysis. NPG-based electrocatalysts have exhibited notable properties towards oxygen reduction reaction (ORR), methanol oxidation reaction, formic acid oxidation reaction and related polymer electrolyte membrane fuel cells. In this work, structure dependent activity and durability towards ORR on NPG supported Pt (NPG-Pt) were investigated, because of the key roles of ORR in various applications such as fuel cell, metal-air batteries and H 2 O 2 generations. Typical NPG-Pt electrocatalysts with epitaxially monolayer, two-layer Pt shells and Pt nanoparticles were selected and systematically investigated relative to commercial Pt/C (20%, JM). The results reveal that all the NPG-Pt catalysts even the sample with only monolayer Pt i.e. Pt loading of 1.1 μg cm−2 mainly exhibit 4-electron ORR pathway without any H 2 O 2 yield, while commercial Pt/C with loadings lower than 2.4 μg cm−2 will favor H 2 O 2 generation which is harmful for the long-term stability. According to the performance stability, conventional accelerated degradation tests reveal that NPG-Pt with two-layer Pt shell (NPG-Pt 2) exhibits the best stability ascribed to the strong metallic bond between Au and Pt. The mass ORR activity of this catalyst is almost unchanged (∼2% reduction) after 30000 cycles potential sweeping while the mass ORR activity of Pt/C with Pt loading of 20 μg cm−2 loses ∼60%. Therefore, NPG-based electrocatalysts present a good activity and stability than common nanoparticle electrocatalysts and developing nanoporous structure but cheap metal based electrocatalysts is a perspective way for cost reduction for commercial applications in energy storage and conversion field. [ABSTRACT FROM AUTHOR]

Abstract In this study, we used ground-measured air pollutants and various remote sensing and meteorological datasets to explore the possible causes of the severe particulate matter (PM) pollution episodes of October and November 2015 in Northeast China. The three pollution episodes in different regions were elaborately characterized by analyzing the time variation of PM 2.5 and other pollutants, e.g., CO, NO 2 , and SO 2. The results from MODerate-resolution Imaging Spectrometer (MODIS) revealed that during the study period, dramatic crop residue burning occurred in Northeast China. Combining its time variation and spatial distribution with air pollutants, the crop residue burning was inferred to have a direct influence on the first and second pollution episodes, especially in Heilongjiang Province. Since a cold wave swept Northeast China beginning on 4th November, the PM pollutants were assumed to be transported southward. This assumption was further verified by the backward and forward trajectory models. Additionally, the suddenly increased relative humidity beginning on 7th November and the week of no wind after the cold wave also greatly contributed to the most severe pollution of Liaoning and Jilin on approximately 8th November. Lastly, we compared air quality indexes and pollutants from remote sensing with ground-measured datasets; the results indicated that there were certain correlations and spatial consistency between the two types of datasets, except for UVAI, which is meaningful to the area without an effective ground monitoring network. Highlights • Both ground-measured and remote sensing datasets are used for PM pollution analysis. • Effective method to extract crop residue burning spots from MODIS was used. • Crop residue burning contributed to the pollution episode in Northeast China. • Meteorological conditions have been taken into consideration. • Various factors jointly induced the worst PM pollution episode in November 2015. [ABSTRACT FROM AUTHOR]

The hydrocarbon generation potential of continental source rocks in the Carboniferous-Permian (C-P) coal-bearing stratum in the Qinshui Basin were systematically analyzed in this paper. Ro of the C-P source rocks is mainly distributed between 1.5% and 2.5%. The coal rock belongs to a typical type III organic matter, while the mudstone mainly contains type III organic matter and a small proportion of type II2 organic matter. Moreover, The geochemical characteristics of the source rock kerogen was analyzed in detail. Finally, an evaluation standard for hydrocarbon generation potential of the C-P continental source rocks was proposed. [ABSTRACT FROM AUTHOR]

Abstract Strike-slip fault zones are an important type of structure formed during continental orogenic events. Exploring the influence of strike-slip faults on the distribution of natural gas by using the 3D finite element method (FEM) is a frontier in the field of geoscience. In this paper, the effects of strike-slip faults on the heterogeneity of in situ stress and reservoir quality were systematically studied in a shallow commercial coalbed methane reservoir in the Shanxi Formation in the southern Qinshui Basin. Systematic 3D FEM modeling and in situ stress evaluation of a highly developed strike-slip fault zone were conducted. The results indicate that the simulated in situ stress distributions of σ H , σ h and σ v in the target layer present ranges of 10–55 MPa, 3–23 MPa and 5–30 MPa, respectively, which are consistent with acoustic emission and hydraulic fracturing measurements. Along the strike-slip faults, the distribution of horizontal in situ stress is mainly affected by the fault length and vertical throw. The stress magnitude differs greatly between the two sides of a given strike-slip fault, affecting the compaction degree and petrophysical properties of the gas-bearing reservoir on both sides of the fault. Along the strike of a given strike-slip fault, the minimum horizontal in situ stress exhibits distinct segmentation characteristics, which affect the distribution of wells with a higher and lower yields. For the 2 s-order faults (the Sitou and Houchengyao faults), wells with a higher gas production capacity are typically located on the northwestern side of the faults. In the middle and southern sections of the Sitou-Houchengyao strike-slip fault zone, both highly concentrated faults and large-scale opening faults (basement and surface faults) produce greater stress concentrations, and the gas production capacity of the gas wells in these areas is poor. When the main strike direction of the faults is consistent with the loading direction of the boundary stress, the stress concentration is relatively low; whereas, the stress concentration increases as the angle between the main fault strike and the loading direction increases. The shear stress of the target layer is characterized by clockwise rotation, which is an important control on the stress heterogeneity of the strike-slip faults in the study area. Highlights • 3D FEM modeling of a highly developed strike-slip fault zone. • Effects of strike-slip faults on stress heterogeneity. • Influence of strike-slip faults on the distribution of natural gas. [ABSTRACT FROM AUTHOR]

Abstract The tight gas sandstone reservoirs in the Paleozoic of the Sulige gas field in China are highly heterogeneous, and fractures are key factors for stable reservoir production. Low-amplitude folds or nose-like structures are widely developed in the Upper Paleozoic strata in this area. To effectively predict gas well productivity, in this paper, a 3D FEM numerical simulation based on the deformation and energy variation of the rock mass was used to predict the "sweet spots" of gas well productivity in a tight gas sandstone reservoir using the He8 segment of the Middle Permian Xiashihezi Formation in the Central Sulige block as an example. The paleotectonic stress field of the study area during the maximum episode of compression in the Yanshanian movement was restored, and the two rupture parameters of the integrated rupture rate (I F) and strain energy density (U) were constructed. The strain energy density distribution has a high correlation with gas well productivity, indicating that it can better predict the rock rupture degree in low-amplitude tectonic zones. A complex relationship exists between the strain energy density distribution and low-amplitude folds. The high strain energy density zones are mainly distributed among the high positions and wing areas of the low-amplitude fold zone, but the top area of the low-amplitude fold does not necessarily have a high strain energy density. Portions of the high strain energy density zones are located in the gentle tectonic zone, located near but outside the low-amplitude fold zone. The strain energy in these gentle tectonic zones with a high strain energy density value is relatively high, and the rock mass is prone to rupture. This study is of great value in enriching the prediction of "sweet spots" in tight gas sandstone reservoirs in low-amplitude tectonic zones worldwide. Highlights • Strain energy density distribution in low-amplitude tectonic zone. • 3D FEM simulation study. • Effect of strain energy distribution on gas well productivity. [ABSTRACT FROM AUTHOR]

Abstract We comprehensively analyzed the temporo-spatial changes in the CO 2 concentrations in Australia from June 2009 to December 2016 using greenhouse gas monitoring satellites, Greenhouse Gases Observing Satellite (GOSAT) and Orbiting Carbon Observatory-2 (OCO-2). Regarding the spatial distribution, the CO 2 concentration in central Australia was always higher than that of other regions, and the lack of precipitation in this region is thought to be one of the main causes of this increased concentration. By combining the results with the Köppen-Geiger climate classification, a subtle relationship between the spatial distribution of CO 2 and various climate types were found. Precipitation, Sea Surface Temperature (SST), phytoplankton around the coastal region, vegetation cover and other factors jointly affected the spatial CO 2 concentration in Australia. Moreover, the results indicated that the abnormal SST in the 4 Niño zones would affect the precipitation and vegetation growth in Australia and the total chlorophyll in the equatorial Eastern Central Pacific Ocean, which would in turn influence carbon cycling in Australia. According to the Niño-3 and Niño-3.4 indices, two El Niño-Southern Oscillation (ENSO) events occurred during the study period. The CO 2 increase rate decreased during the period of the 2011 La Niña, while the CO 2 increase rate increased during the period of the 2015 El Niño. With the global CO 2 concentration as the background, the abnormal change of CO 2 in Australia was analyzed. Lastly, the results showed that SST around Australia, precipitation, vegetation, ENSO events, oceanic chemical processes and bushfires were assumed to directly or indirectly influence the temporal changes in CO 2 in this region. Highlights • Tempo-spatial distribution of CO 2 is analyzed by combining GOSAT with OCO-2. • The temporal change of CO 2 is analyzed with various factors. • The precipitation and vegetation change in Australia is analyzed with ENSO events. • The spatial distribution of CO 2 is analyzed with different climate types. [ABSTRACT FROM AUTHOR]

• Simulation results explains reason for frozen shape deformation of nanofluid droplet. • Suspended particles are simulated in multiphase fluid during phase change process. • Dynamic motion and aggregation characteristics of a large number of particles are simulated. The freezing process of a sessile nanofluid droplet has been reported to behave differently from a pure sessile water droplet in terms of freezing dynamics and the final shape of the ice droplet. When nanoparticles are added to the water droplet, instead of forming a pointed tip on the top, the completely frozen droplet exhibits a flat plateau shape. To investigate this unique scenario, we developed a lattice Boltzmann (LB) model that combines the multiphase solidification model (MSM) with the immersed boundary method (IBM). The MSM is based on our previous work of simulating the freezing of a pure droplet, while the IBM is used to handle the interaction forces between the suspended particles and the different phases in the freezing droplet. Using this LB model, we succeeded in simulating the formation process of the frozen plateau shape. The simulation takes into account the dynamics of the dispersed particles, including their expulsion from the propagation freezing front and their segregation, which brings the liquid water to the edge. We compared the simulated freezing shape profiles with the experimental images and found that the shape forms in a similar manner. We then used the developed model to explore more cases, considering the effects of droplet contact angles and particle volume concentration. Results show that the distribution of particles and final droplet height depend on the surface wettability, as the freezing front exhibits a concave/convex shape on hydrophilic/hydrophobic surfaces, resulting in different particle separation distributions on the freezing front interface. Furthermore, our simulation results confirm the experimental conclusion that the plateau size on the frozen top increases with particle concentration and appears to be independent of the initial droplet contact angle. [Display omitted] [ABSTRACT FROM AUTHOR]

Purpose: Convolution operator-based neural networks have shown great success in medical image segmentation over the past decade. The U-shaped network with a codec structure is one of the most widely used models. Transformer, a technology used in natural language processing, can capture long-distance dependencies and has been applied in Vision Transformer to achieve state-of-the-art performance on image classification tasks. Recently, researchers have extended transformer to medical image segmentation tasks, resulting in good models. Methods: This review comprises publications selected through a Web of Science search. We focused on papers published since 2018 that applied the transformer architecture to medical image segmentation. We conducted a systematic analysis of these studies and summarized the results. Results: To better comprehend the benefits of convolutional neural networks and transformers, the construction of the codec and transformer modules is first explained. Second, the medical image segmentation model based on transformer is summarized. The typically used assessment markers for medical image segmentation tasks are then listed. Finally, a large number of medical segmentation datasets are described. Conclusion: Even if there is a pure transformer model without any convolution operator, the sample size of medical picture segmentation still restricts the growth of the transformer, even though it can be relieved by a pretraining model. More often than not, researchers are still designing models using transformer and convolution operators. [ABSTRACT FROM AUTHOR]

In this work, we discovered that bis(trimethylsilyl)acetylene (BTMSA) could be synthesized by the reaction of calcium carbide (CaC2) directly with N‐(trimethylsilyl)imidazole (TMSIm) in dichloromethane using CuBr as the catalyst, and reaction could occur efficiently at 100 °C. Control experiment indicated that the reaction did not proceed via acetylene pathway. As far as we know, this is the first work for BTMSA synthesis by direct reaction of CaC2 and a silylation reagent under mild conditions. [ABSTRACT FROM AUTHOR]

Objective The prognostic value of vimentin expression in Gastric Cancer (GC) has been assessed for years while the results are still in dispute. Thus, we performed a meta-analysis to determine the effect of vimentin immunohistochemical (IHC) expression on the prognosis of GC. Methods Literature searches were performed in PubMed and Embase. The meta-analysis examined the association of vimentin IHC expression with prognosis and clinicopathological characteristics of GC patients. Results In total, ten studies involving 1598 cases were enrolled in this meta-analysis. Vimentin positive expression was significantly correlated with poor overall survival (OS) in GC patients (HR = 2.05, 95% CI: 1.29–3.24) but there was a significant degree of heterogeneity (I 2  = 77%, P = 0.0006). Subgroup analysis indicated that vimentin expression had an unfavorable impact on OS in Chinese patients (HR = 2.43, 95% CI: 1.30–4.55). Moreover, vimentin positive expression rates was significantly associated with age, tumor location, TNM stage and lymph node metastasis. However, vimentin positive expression rates did not correlate with gender, grade of differentiation, vascular invasion, the depth of invasion, hepatic metastasis or peritoneal metastasis. Conclusions Positive vimentin expression could serve as a poor prognostic marker in GC. [ABSTRACT FROM AUTHOR]

We used OCO-2 products and considered three factors that potentially affect CO2 concentration in Indonesia: sea surface temperature (SST), forest fires and vegetation. From 2014 to 2016, CO2 concentration in Indonesia showed a trend of increase, which is consistent with the global increase reported by the Greenhouse Gases Observing Satellite (GOSAT) Project. As an archipelago country, the results indicate that SST has a direct effect on the CO2 concentration in Indonesia. Their changing exhibits similar fluctuations; meanwhile, CO2 concentration and SST also presented positive correlation. In 2015, the number of fire hotspots suddenly increased to 140,699, because of occurrence of the worst forest fire. Due to special geographic conditions, forest fires did not induce CO2 concentration changes in Indonesia, but CO2 concentration in the corresponding islands showed a trend of increase. CO2 concentration increased in Kalimantan during the occurrence of forest fire in September-October 2014, and CO2 concentration increased in Kalimantan and Sumatra during the occurrence of forest fire in September-October 2015. Vegetation indices were stable and presented no correlation with CO2 concentration. This study demonstrated that OCO-2 is capable of monitoring CO2 concentration at a regional scale; additionally, an effective method for using OCO-2 Level 2 products is proposed. [ABSTRACT FROM AUTHOR]

Aim: The aim of this study was to investigate whether CXCR3 expression is associated with: infiltration of dendritic cells (DCs) and CD4+ and CD8+ tumor-infiltrating lymphocytes (TILs); various clinical features; and overall survival (OS) of patients diagnosed with gastric cancer (GC). Materials and Methods: The study included 169 GC specimens and 91 corresponding paracancerous tissues. Immunohistochemistry was conducted to determine the expression of CXCR3 and the presence of DCs and CD4+ and CD8+ TILs. Statistical analyses were done using SPSS 17.0 software. Results: CXCR3 expression in GC tissues was significantly higher than in paracancerous tissues ( p < 0.001). Higher CXCR3 expression was associated with increased DC and both CD8+ and CD4+ TIL infiltration ( p = 0.003, p = 0.008, and p = 0.016, respectively). In contrast, low CXCR3 expression was correlated with greater tumor invasion depth, III/IV TNM stage, lymph node metastasis, and more poorly differentiated tumor cells in GC patients ( p = 0.001, p = 0.005, p = 0.037, and p = 0.004, respectively). Univariate analysis indicated that patients with high CXCR3 expression and high DC and CD8+ TIL infiltration had longer OS (log-rank test, p < 0.001, p = 0.018, and p = 0.001, respectively). Univariate and multivariate analyses indicated that CXCR3 expression was an independent prognostic factor for OS ( p < 0.001, in both cases). Conclusion: The results of this study indicate that CXCR3 overexpression in GC is associated with increased DC and TIL infiltration and improved OS, and thus could be further exploited as a biomarker of favorable prognosis and a therapeutic target in GC. [ABSTRACT FROM AUTHOR]

Background/Aims: Retinoid receptors and retinoic acid were reported to be down-regulated in pancreatic duct adenocarcinoma (PDAC) compared to normal pancreas. Yet the mechanism of the down-regulation of retinoid receptors is not well defined. The aim of this study was to find out whether selected dysregulated miRNAs in PDAC are responsible for the decreased level of retinoid receptors. Methods: Bioinformatics, real-time PCR, western blot analysis as well as molecular manipulation with miRNA in cells of PDAC were carried out. Results: We first performed bioinformatics research to identify conserved target sequences for deregulated miRNAs within the 3'UTR region of retinoid receptor mRNA. This research revealed binding sites for miR-138, -27a, -27b, -206, -613, -9-5p, -27a/b-3p and -27a. Next, we investigated the expression of selected retinoid receptors and miRNAs in PDAC cell lines and in the Human Pancreatic Duct Epithelial (HPDE) cell line. Further, we investigated the effects of modifying expression levels of selected miRNAs using miRNA inhibitors or mimics. We demonstrated that none of these miRNAs can target the selected retinoid receptors in vitro. Conclusions: miR-27a, miR-27b, miR-9, miR10a and miR-10b were up-regulated in PDAC cells compared to HPDE cells. The up-regulation of these miRNAs was not responsible for the down-regulation of RARa, RARß, RXRa and RXRß in PDAC cells. [ABSTRACT FROM AUTHOR]

In this paper, the supercritical gas molecule adsorption characteristics of methane in shale are quantitatively described by using the lattice theory. The results show that the methane adsorption capacity predicted by this theory is high, with the average absolute error 0.003 3 mmol·g−1. There is a near-linear positive relationship between the adsorption potential between methane and the solid surface (ϵs) and the experimental temperature. The value of the average potential between the adsorbate molecules (ϵa) is distributed in −0.841–1.791 kJ·mol−1, and the absolute value of ϵais significantly smaller than the absolute value of ϵs, indicats that the potential energy between the adsorbate molecules is significantly smaller than that between the adsorbate molecules and the pore surface of shale. When the temperature is relatively low (T= 308.55 K), the value of ϵs/ϵais 7.5 times; with the increases of the temperature, the magnification will gradually decrease and keep stabilize (3.37 times). [ABSTRACT FROM PUBLISHER]

Skirted spudcan foundations can provide a considerable bearing capacity and moment fixity for resisting the complex combined vertical, horizontal, and moment loadings arising from the harsh environment in the offshore oil and gas industry. These potential benefits are conducive to the extension of mobile jack-up drilling rigs into deep water. In this study, a series of probe tests were carried out using finite element analysis to investigate the effects of the skirt length and embedment depth on the bearing capacity of skirted spudcan foundations in soft clay under combined loading. The results indicate that both the skirt length and the embedment depth can significantly affect the behavior of a skirted spudcan and apparently improve the various bearing capacities under combined loading. As the skirt length and embedment depth increase, the failure envelope's size gradually expands and the failure envelope's shape changes accordingly. A spudcan with a skirt length of 0.25 D embedded in about 2 D of sediments is suggested to obtain an optimal application in practice. A closed-form algebraic expression was derived to interpret and predict the behavior of skirted spudcan foundations, which properly considers the effects of the skirt length and embedment depth. • The undrained bearing capacities of embedded skirted spudcan foundations under combined loading in soft clay were investigated. • The effects of the skirt length and the embedment depth on the various bearing capacities were discussed. • A spudcan with skirt length of 0.25 D embedded at a depth of about 2 D was suggested to obtain optimal application in practice. • A closed-form algebraic analytical expression was proposed, which can describe the capacity envelope under combined loading and it is applicable to each skirt length and embedded depth. [ABSTRACT FROM AUTHOR]

With the continuous growth in global energy demand, research and development of unconventional oil and gas reservoirs have become crucial in the field of energy. This study focuses on the Chang 3 reservoir of the Yanchang Formation in the Ordos Basin, Weibei Oilfield, China. This reservoir is a typical tight sandstone reservoir, and its microscopic pore structure and displacement mechanism are essential for the efficient development of tight oil. However, the reservoir faces challenges such as complex microscopic pore structures and unclear displacement mechanisms, which hinder the efficient development of tight oil. In light of these challenges, through various studies including core observation, high-pressure mercury injection tests, water flooding experiments, oil-water two-phase relative permeability measurements, and stress sensitivity experiments, it was found that the Chang 3 reservoir exhibits strong microscopic heterogeneity. The pore-throat distribution characteristics mainly present two types: single peak and double peak, with the double peak type being predominant. The reservoir was classified and evaluated based on these characteristics. The improved injection ratio and properties enhance oil displacement efficiency, but an increase in irreducible water saturation has a negative impact on efficiency. The stress sensitivity of the reservoir fluctuates between weak and strong, with permeability being sensitive to net confining pressure. It is recommended to pay particular attention to the stress-sensitivity characteristics during reservoir development. The research results provide a scientific basis for the optimized development of tight oil reservoirs in this region, promote the sustainable development of unconventional oil and gas resources, and have significant theoretical and practical implications. [ABSTRACT FROM AUTHOR]

Gypsum rocks have extremely low permeability and good pressure sealing capability, and they are widely distributed in different strata all over the world. A deep-thick gypsum cap rock is developed in the Paleogene formation of the southwestern Tarim Basin in China. The regions below the gypsum rocks have huge potential for oil and gas resources. Casing deformation and blockage during tripping operations often occur during the drilling process in the gypsum bed, which severely affects the efficient drilling of deep oil and gas. Therefore, it is necessary to comprehensively assess the geostress field of gypsum cap rocks under high-stress background conditions. Through triaxial synchronized mechanical and acoustic testing experiments, high-stress formation environments were simulated and the mechanical parameters of gypsum rocks were obtained. We used dispersion correction technology to transform the measured high-frequency (1 MHz) wave velocities of the samples to the wave velocities of well-logging frequency (20 kHz). The transformed wave velocities can be used for the well-logging assessment of rock mechanical parameters and geostress. We built well-logging interpretation models for the shear-wave slowness, mechanical parameters and geostress of the Paleogene gypsum rocks. Each model showed high assessment accuracy. Combined with the paleomagnetic analysis of the Paleogene gypsum bed and the results of the fast shear-wave direction analysis, radial expansion position analysis and induced fracture analysis on the reservoir below the Paleogene gypsum bed, we suggest that the direction of geostress in the study region is NW10°. Three-dimensional finite element method was used to simulate the geostress field of the gypsum bed. The Paleogene formation in the study region does not have faults. The geostress distribution of the gypsum rock layer is mainly controlled by structural relief, burial depth, and lithology. This study provided a typical example of a comprehensive assessment of the geostress field of deep-thick gypsum cap rocks. [ABSTRACT FROM AUTHOR]

Deep marine tight sandstone oil reservoirs are the subject of considerable research around the world. This type of reservoir is difficult to develop due to its low porosity, low permeability, strong heterogeneity and anisotropy. A marine tight sandstone oil reservoir is present in the Silurian strata in the northern Tazhong area of the Tarim Basin, NW China, at a depth of more than 5000 m. The porosity is between 6% and 8%, and the gas permeability is between 0.1 and 1 × 10 −3 μm 2 . The features of this type of reservoir include the poor effects of conventional fracturing modifications and horizontal wells, which can lead to stable and low levels of production after staged fracturing. Here, we conduct a comprehensive evaluation of the mechanical properties of the rock and the in situ stress of the target tight sandstones by using numerous mechanical and acoustic property tests, conducing crustal stress analysis and using data from thin section observations. The dispersion correction technique is used to transform velocity at the experimental high frequency (1 MHz) to velocity at the logging frequency (20 kHz). The logging interpretation models of the transverse wave offset time, mechanical parameters and in situ stress are calculated, and each model represents a high precision prediction. Simulating the in situ stress field of the Silurian strata using a three-dimensional finite element method demonstrates that the average error between the simulation result and the measured value is less than 6%. The planar distribution of each principal stress is mainly controlled by the burial depth and fault distribution. By conducting in situ stress orientation analysis for the target layer via the analysis of paleomagnetism, borehole enlargement, fast shear wave orientation and stress field simulation, we show that the direction of the maximum horizontal stress is N45E. In this paper, a typical and successful comprehensive evaluation of the stress field of the deep tight sandstone oil reservoir is provided. [ABSTRACT FROM AUTHOR]

The health burden from exposure to ambient fine particulates (PM 2.5) in Equatorial Asia is substantially affected by the peatland fires in Indonesia, but the long-term health effect of the fires on local inhabitants is unclear. In this study, PM 2.5 -associated excess mortality in Equatorial Asia over the past 30 years (1990–2019) was estimated and then the health effect of biomass burning was identified. The PM 2.5 -related death in Equatorial Asia almost tripled from 113 (95% confidence interval, 100–125) thousand in 1990 to 337 (300–373) thousand in 2019, with a rate of increase of 6.4 (6.2–6.9) thousand/yr. The intense biomass burning between 1990 and 2019 was estimated to have induced 317 (282–348) thousand excess deaths in the study regions, with excess deaths mainly occurring in the El Niño years, such as in 1997, 2006, 2015 and 2019. Although the remote sensing data and emission inventories both reveal that the effective control measures have reduced biomass burning intensity in Equatorial Asia (especially in Sumatra and Borneo), the corresponding health benefit has been offset by variations in demographic factors, i.e., population and age structure. Over the same period, fossil fuel emissions continued to increase rapidly. Thus, more stringent and ambitious policies are required to reduce the health burden from biomass burning and anthropogenic emissions simultaneously to maximize the health benefits from government measures and policies. • The PM 2.5 -related death in Equatorial Asia almost tripled from 1990 to 2019. • Biomass burning intensity in Equatorial Asia has substantially declined. • The benefits of the improved air quality were offset by variations in the demographic factors. • The intense BB from 1990 to 2019 is estimated to have induced 317 thousand of excess deaths. [ABSTRACT FROM AUTHOR]

A halophilic archaeal strain, YJ-18-S1, was isolated from Yangjiang marine solar saltern, Guangxi Province, China. Cells were pleomorphic, stained Gram-negative and formed red-pigmented colonies on agar plates. Strain YJ-18-S1 was able to grow at 20-55 °C (optimum 37 °C), at 0.9-4.8 M NaCl (optimum 2.6 M NaCl), at 0.005-1.0 M MgCl (optimum 0.3 MgCl) and at pH 5.5-8.5 (optimum pH 7.0). The cells were lysed in distilled water, and the minimal NaCl concentration to prevent cell lysis was found to be 5 % (w/v). The major polar lipids of the strain were phosphatidic acid, phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate and sulfated mannosyl glucosyl diether. The 16S rRNA gene and rpoB′ gene of strain YJ-18-S1 were phylogenetically related to the corresponding genes of Halorubrum members (94.3-98.0 and 86.7-96.1 % similarities, respectively). The DNA G+C content of strain YJ-18-S1 was 66.2 mol%. The phenotypic, chemotaxonomic and phylogenetic properties suggested that strain YJ-18-S1 (=CGMCC 1.12554 = JCM 30030) represents a new species of Halorubrum, for which the name Halorubrum rutilum sp. nov. is proposed. [ABSTRACT FROM AUTHOR]

The diamond thick layers prepared using chemical vapor deposition (CVD) methods have been treated at high pressures and high temperatures (HP-HT). It was found that the Vickers hardness of the HP-HT treated bulks was nearly two times as high as that of the starting CVD diamond samples. The hardness of the samples treated at 8 GPa and 1800°C is ∼80 GPa at a loading force of 49 N, close to that of the single-crystal diamond (∼100 GPa). In addition, the oxidation resistance of CVD diamond samples was also enhanced greatly after HP-HT treatments, and the diamondization of sp2bonded carbon in the CVD diamond samples could occur at 7–8 GPa and 1600–1800°C. The HP-HT conditions of diamondization in our works are much lower than the case of the graphite-to-diamond direct transformation without the presence of catalyst (>15 GPa and 2000°C). [ABSTRACT FROM PUBLISHER]